title: Estimated drinking water fluoride exposure and risk of hip fracture: a cohort study.
abstract: The cariostatic benefit from water fluoridation is indisputable, but the knowledge of possible adverse effects on bone and fracture risk due to fluoride exposure is ambiguous. The association between long-term (chronic) drinking water fluoride exposure and hip fracture (ICD-7-9: '820' and ICD-10: 'S72.0-S72.2') was assessed in Sweden using nationwide registers. All individuals born in Sweden between January 1, 1900 and December 31, 1919, alive and living in their municipality of birth at the time of start of follow-up, were eligible for this study. Information on the study population (n = 473,277) was linked among the Swedish National In-Patient Register (IPR), the Swedish Cause of Death Register, and the Register of Population and Population Changes. Estimated individual drinking water fluoride exposure was stratified into 4 categories: very low, < 0.3 mg/L; low, 0.3 to 0.69 mg/L; medium, 0.7 to 1.49 mg/L; and high, ≥ 1.5 mg/L. Overall, we found no association between chronic fluoride exposure and the occurrence of hip fracture. The risk estimates did not change in analyses restricted to only low-trauma osteoporotic hip fractures. Chronic fluoride exposure from drinking water does not seem to have any important effects on the risk of hip fracture, in the investigated exposure range.
authors.affiliation: Clinical Epidemiology Unit, Karolinska Institutet and Karolinska University Hospital, Solna, Sweden.
authors.forename: P
authors.initials: P
authors.lastname: Näsman
authors.forename: J
authors.initials: J
authors.lastname: Ekstrand
authors.forename: F
authors.initials: F
authors.lastname: Granath
authors.forename: A
authors.initials: A
authors.lastname: Ekbom
authors.forename: C M
authors.initials: CM
authors.lastname: Fored
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D002327:Cariostatic Agents / Q000032:analysis*; D015331:Cohort Studies; D004781:Environmental Exposure; D005260:Female; D005459:Fluorides / Q000032:analysis*; D005500:Follow-Up Studies; D006620:Hip Fractures / Q000453:epidemiology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D058866:Osteoporotic Fractures / Q000453:epidemiology; D012042:Registries; D018570:Risk Assessment; D013548:Sweden / Q000453:epidemiology; D014881:Water Supply / Q000032:analysis*
chemical_list: D002327:Cariostatic Agents; D005459:Fluorides
keywords: Sweden; chronic exposure; epidemiology; nationwide cohort study; relative risk